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The Catalytic Version of Stoichiometric Organic Synthesis Pp. 5-14
Hideki Amii
[Abstract] [Full text article]

A Simple, High Yield Route to cis-4-(N-Alkylamino)-L-Prolines Pp.15-17
Timothy P. Curran, Kevin A. Marques and Segufta I. Bilimoria
[Abstract] [Full text article]

First Efficient One-Pot Synthesis of Tetrahydropyrrolo[2,3-d]azocines and Tetrahydroazocino[4,5-b]indoles Pp. 18-20
Leonid G.Voskressensky, Tatiana N. Borisova, Tatiana A. Soklakova, Larisa N. Kulikova, Roman S. Borisov and Alexej V. Varlamov
[Abstract] [Full text article]

Enantiopure Bicyclic Piperidinones: Stereocontrolled Cycloadditions Pp. 21-24
A.G. Brewster, S. Broady, E. Glenn, S.A. Hermitage, M. Hughes, M.G. Moloney and G. Woods
[Abstract] [Full text article]

A Caveat on the Use of 2-Chloro-4,6-dimethoxy-1,3,5-triazine for the Synthesis of 4,4-Dimethyl-2-R-2-Oxazolines Pp. 25-28
Robert A. Gossage and Amber L. Sadowy
[Abstract] [Full text article]

Synthesis and Transformations of New Spiro-4-piperidines. Acetyl Migration in 1-Acetyl-1’-Benzyl-4-Methyl-3,4-Dihydrospiro[(1H)quinoline-2,4’-piperidines] Under Debenzylation Conditions Pp. 29-32
Vladimir V. Kouznetsov, Basilio Diaz P., Clara Marcela Sanabria M., Leonor Y. Vargas M., Juan Carlos Poveda, Elena E. Stashenko, Ali Bahsas and Juan Amaro-Luis
[Abstract] [Full text article]

Chiral Acetylenic Sulfoxide in Organic Synthesis: Addition of Chiral Secondary Amines Pp. 33-36
Sujun Yan, K.T. Lam, K.T. Mo, W.Y. Wong, W.H. Chan and Albert W.M. Lee
[Abstract] [Full text article]

Nucleophilic Carbenes of Pyrazoles Starting from Pseudo-Cross-Conjugated Mesomeric Betaines Pp. 37-39
Andreas Schmidt and Tobias Habeck
[Abstract] [Full text article]

Reaction Systems Peripheral to the 1:2 Mannich Condensation Reaction between o-Phthalaldehyde and Primary Amine Pp. 40-43
I. Takahashi, K. Nishiuchi, R. Miyamoto, M. Hatanaka, H. Uchid, K. Isa, A. Sakushima and S. Hosoi
[Abstract] [Full text article]

One-Pot, Regioselective Synthesis of 1,3,5 Trisubstituted Hydantoins by Domino Condensation/aza-Michael/O?N acyl Migration of Asymmetric Carbodiimides with a,b-Unsaturated Carboxylic Acids Pp. 44-46
Alessandro Volonterio and Matteo Zanda
[Abstract] [Full text article]

Fused 1,3-oxazolidine-2-thiones on Ketohexose Backbones: Functional Modulation Processes Pp. 47-50
Arnaud Tatibouet, Ana C. Simao and Patrick Rollin
[Abstract] [Full text article]

Why has Cerium (III) Triflate been Forgotten Among the Catalysts for the Friedel-Crafts Acylation? Pp. 51-53
Giuseppe Bartoli, Antonio De Nino, Renato Dalpozzo, Loredana Maiuolo, Monica Nardi, Antonio Procopio and Antonio Tagarelli
[Abstract] [Full text article]

A Novel Mechanism of Specificity of Response in Ratiometric Fluorescence Sensing of d10 Metal Ions Pp. 54-56
Scott A. Van Arman, Thomas M. Sisk and David M. Zawrotny
[Abstract] [Full text article]

A Remarkable Zirconium(IV) Chloride Catalyzed Highly Selective Deprotection of t-Butyldimethylsilyl (TBS) Ethers in Presence of t-Butyldiphenylsilyl (TPS) Ethers Pp. 57-60
G.V.M. Sharma, B. Srinivas and Palakodety Radha Krishna
[Abstract] [Full text article]

Chemoselective Carbonyl Benzylation Mediated by Zn/CdCl2/InCl3 in Tap Water Pp. 61-64
Cunliu Zhou, Jiaoyang Jiang, Yuqing Zhou, Zhen Xie, Qian Miao and Zhiyong Wang
[Abstract] [Full text article]

Enantioselective Copper-catalysed Conjugate Addition of Diphenylzinc to Cyclohexenone Pp. 65-67
Xiao-yu Wu, Xiang-guo Li and Gang Zhao
[Abstract] [Full text article]

A DFT Analysis of the Strain-Induced Regioselective[2+2]Cycloaddition of Benzyne Possessing Fused Four-Membered Ring Pp. 68-73
L.R. Domingo, P. Perez and R. Contreras
[Abstract] [Full text article]

Model Studies Towards Alternative Cross-Linking of Unsaturated Polyesters Pp. 74-76
Thomas Straub, Martin Brunner and Ari M.P. Koskinen
[Abstract] [Full text article]

Imidazolium Dichromate Adsorbed on Alumina: A Convenient and Inexpensive Reagent for the Cleavage of C=N Functionalities Pp. 77-78
Surya Kanta De
[Abstract] [Full text article]

A Simple Approach to DC-Cholesterol, its Analogues and Vitamin D-Based Cationic Lipids for Gene Therapy Pp. 79-82
Armandodoriano Bianco, Francesco Bonadies, Raffaella Napolitano and Giancarlo Ortaggi
[Abstract] [Full text article]

Design and Synthesis of a New Furanosic Sialylmimetic as a Potential Influenza Neuraminidase Viral Inhibitor Pp. 83-88
A. Bianco, M. Brufani, D.A. Dri, C. Melchioni and L. Filocamo
[Abstract] [Full text article]

Baker's Yeast Reduction of PEG-Linked Acetoacetate Pp. 89-91
G.M. Bonora, S. Drioli, C. Forzato, P. Nitti and G. Pitacco
[Abstract] [Full text article]

Abstracts

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The Catalytic Version of Stoichiometric Organic Synthesis
Hideki Amii
[Full text article]

This short review focuses on the impressive examples of endeavors to make stoichiometric reactions catalytic. The strategies employed encompass the reuse of waste coproducts to achieve the catalytic cycles and to reduce the amounts of reagents of the transformations. Several methodologies for in situ regeneration of active agents are highlighted.

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A Simple, High Yield Route to cis-4-(N-Alkylamino)-L-Prolines
Timothy P. Curran, Kevin A. Marques and Segufta I. Bilimoria
[Full text article]

Reaction of 1 equivalent of N-a-acetyl-cis-4-azido-L-proline with 1 equivalent of an aldehyde and a catalytic amount of Pd-C under an H2 atmosphere cleanly and efficiently yields the corresponding N-a-acetyl-cis-4-(N-?-alkylamino)-L-proline derivative.

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First Efficient One-Pot Synthesis of Tetrahydropyrrolo[2,3-d]azocines and Tetrahydroazocino[4,5-b]indoles
Leonid G.Voskressensky, Tatiana N. Borisova, Tatiana A. Soklakova, Larisa N. Kulikova, Roman S. Borisov and Alexej V. Varlamov
[Full text article]

A new efficient one-pot protocol for the synthesis of tetrahydropyrrolo[2,3-d]azocines and tetrahydroazocino[4,5-b]indoles starting from ready-available tetrahydropyrrolo[3,2-c]pyridines and tetrahydropyrido[4,3-b]indoles correspondingly and dimethylacetylene dicarboxylate or ethyl propiolate is being offered.

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Enantiopure Bicyclic Piperidinones: Stereocontrolled Cycloadditions
A.G. Brewster, S. Broady, E. Glenn, S.A. Hermitage, M. Hughes, M.G. Moloney and G. Woods
[Full text article]

The cycloadditions of a [4.3.0]-bicyclic a,b-unsaturated lactam, derived from 6-oxopipecolic acid, have been investigated. Although yields are modest, diastereoselectivity is high; reasons for the low reactivity are postulated, based on experimental observations and molecular modelling.

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A Caveat on the Use of 2-Chloro-4,6-dimethoxy-1,3,5-triazine for the Synthesis of 4,4-Dimethyl-2-R-2-Oxazolines
Robert A. Gossage and Amber L. Sadowy
[Full text article]

The reported synthesis of 4,4-dimethyl-2-R-2-oxazolines from carboxylic acids and 2-amino-2-methyl-1-propanol (1) using 2-chloro-4,6-dimethoxy-1,3,5-triazine (2) via direct coupling/cyclisation is questioned. The results reported herein indicate that the products are actually w–hydroxyamides resulting from dehydrative R-COOH/1 (peptide) coupling only, which has been known to be mediated by 2 for some time.

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Synthesis and Transformations of New Spiro-4-piperidines. Acetyl Migration in 1-Acetyl-1’-Benzyl-4-Methyl-3,4-Dihydrospiro[(1H)quinoline-2,4’-piperidines] Under Debenzylation Conditions
Vladimir V. Kouznetsov, Basilio Diaz P., Clara Marcela Sanabria M., Leonor Y. Vargas M., Juan Carlos Poveda, Elena E. Stashenko, Ali Bahsas and Juan Amaro-Luis
[Full text article]

Synthesis of new dihydrospiro[quinoline-2,4’-piperidines] by a two-step synthetic route based on 4-piperidone imine reactivity is reported. An acetyl migration in 1-acetyl-1’-benzyl-4-methyl-3,4- dihydrospiro[quinoline-2,4’-piperidines] under debenzylation conditions (HCOONH4/Pd/C/MeOH) is found.

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Chiral Acetylenic Sulfoxide in Organic Synthesis: Addition of Chiral Secondary Amines
Sujun Yan, K.T. Lam, K.T. Mo, W.Y. Wong, W.H. Chan and Albert W.M. Lee
[Full text article]

Chiral secondary amines of the 3,4-dimethoxyphenylethyl and the tryptamine system were reacted with chiral acetylenic sulfoxides and achiral acetylenic sulfone. In the case of 3,4-dimethoxyphenylethyl amine, much improved diastereoselectivity (96 : 4) was observed as compared to the reaction of achiral secondary amine with chiral acetylenic sulfoxides.

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Nucleophilic Carbenes of Pyrazoles Starting from Pseudo-Cross-Conjugated Mesomeric Betaines
Andreas Schmidt and Tobias Habeck
[Full text article]

Pyrazolium-3-carboxylates, which belong to the class of pseudo-cross-conjugated heterocyclic mesomeric betaines, decarboxylate to give nucleophilic carbenes, which can be trapped as pyrazolium salts. An aldol addition, a Knoevenagel reaction, and a Cannizzaro-type reaction are presented, which are initiated by the strong basicity of the in situ generated pyrazol-3-ylidene.

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Reaction Systems Peripheral to the 1:2 Mannich Condensation Reaction between o-Phthalaldehyde and Primary Amine
I. Takahashi, K. Nishiuchi, R. Miyamoto, M. Hatanaka, H. Uchid, K. Isa, A. Sakushima and S. Hosoi
[Full text article]

Reaction systems peripheral to the 1:2 condensation reaction between o-phthalaldehyde and primary amine were studied. Newly identified were 1,3-dihydroxyisoindoline, o-iminomethylbenzaldehyde and o-amidiniobenzoate, the last of which exhibited moderate anticancer activity.

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One-Pot, Regioselective Synthesis of 1,3,5 Trisubstituted Hydantoins by Domino Condensation/aza-Michael/O?N acyl Migration of Asymmetric Carbodiimides with a,b-Unsaturated Carboxylic Acids
Alessandro Volonterio and Matteo Zanda
[Full text article]

1,3,5 Trisubstituted hydantoins having two different substituents at the nitrogen atoms could be smoothly prepared by a domino condensation/aza-Michael/O?N acyl migration of asymmetric carbodiimides with activated a,b-unsaturated carboxylic acids. The regiochemical outcome of the process, as well as scope and limits, are discussed.

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Fused 1,3-oxazolidine-2-thiones on Ketohexose Backbones: Functional Modulation Processes
Arnaud Tatibouet, Ana C. Simao and Patrick Rollin
[Full text article]

1,3-Oxazolidine-2-thiones fused to ketohexose backbone were prepared from 1-O-, 1-N- or 1-S-derivatives in reasonable yields. Spontaneous ring closure leads to spiro-tricyclic unexpected aminal and amide structures.

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Why has Cerium (III) Triflate been Forgotten Among the Catalysts for the Friedel-Crafts Acylation?
Giuseppe Bartoli, Antonio De Nino, Renato Dalpozzo, Loredana Maiuolo, Monica Nardi, Antonio Procopio and Antonio Tagarelli
[Full text article]

Cerium is the less rare "rare earth"; its salts are commercially available and inexpensive. However, screening of lanthanide triflates as Lewis acid catalysts in the Friedel-Crafts acylation of aromatics skipped cerium triflate. Now, catalytic Friedel-Crafts acylations of activated benzenes are performed by using cerium (III) triflate as catalyst. For less activated arenes, addition of lithium perchlorate as co-catalyst is required. In all cases aromatic ketones are obtained in very good yields.

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A Novel Mechanism of Specificity of Response in Ratiometric Fluorescence Sensing of d10 Metal Ions
Scott A. Van Arman, Thomas M. Sisk and David M. Zawrotny
[Full text article]

In a 25% methanolic aqueous solution the metal ion specificity of ratiometric fluorescence response of a bis-anthrylpolyamine host is increased versus a purely aqueous medium. It is proposed that the geometry of the host, metal ion size, and hydrophobicity work in concert to give the geometry leading to excimer fluorescence.

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A Remarkable Zirconium(IV) Chloride Catalyzed Highly Selective Deprotection of t-Butyldimethylsilyl (TBS) Ethers in Presence of t-Butyldiphenylsilyl (TPS) Ethers
G.V.M. Sharma, B. Srinivas and Palakodety Radha Krishna
[Full text article]

A highly selective and efficient method for the chemoselective deprotection of t-butyldimethylsilyl (TBS) ethers using 20 mol% of zirconium(IV) chloride as Lewis acid in isopropanol is reported. Remarkable selectivity was observed towards the TBS group deprotection while TPS remains unaffected. The reaction is fast and the conditions are tolerable to a variety of protecting groups, carbohydrates and terpenes. The products are obtained in excellent yields.

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Chemoselective Carbonyl Benzylation Mediated by Zn/CdCl2/InCl3 in Tap Water
Cunliu Zhou, Jiaoyang Jiang, Yuqing Zhou, Zhen Xie, Qian Miao and Zhiyong Wang
[Full text article]

A novel trimetal system (Zn/CdCl2/InCl3) has been developed as an effective mediator in the benzylations of various aldehydes in tap water to afford the corresponding alcohols. It can selectively mediate the benzylation of aldehyde in the presence of ketone. CdCl2 and InCl3 are easily recycled and used in this reaction without further purification.

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Enantioselective Copper-catalysed Conjugate Addition of Diphenylzinc to Cyclohexenone
Xiao-yu Wu, Xiang-guo Li and Gang Zhao
[Full text article]

The copper-catalysed asymmetric conjugate addition of diphenylzinc to 2-cyclohexenone has been carried out with good results. An enantiometric excess of up to 91% was obtained using 5 mol% CuI and 5 mol% phosphine ligand derived from L-proline.

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A DFT Analysis of the Strain-Induced Regioselective[2+2]Cycloaddition of Benzyne Possessing Fused Four-Membered Ring
L.R. Domingo, P. Perez and R. Contreras
[Full text article]

The regioselective [2+2] cycloaddition of a substituted benzyne possessing a fused four-membered ring to a ketene acetal has been theoretically studied. This cycloaddition presents a two-step mechanism that is initiated by the nucleophilic attack to the benzyne to give a zwitterionic intermediate. The analysis performed on the basis of the global and local electrophilicity of reagents correctly explain the observed reactivity and regioselectivity in this system.

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Model Studies Towards Alternative Cross-Linking of Unsaturated Polyesters
Thomas Straub, Martin Brunner and Ari M.P. Koskinen
[Full text article]

Fumaric and maleic acid esters are functionalised with propargylamine. A subsequent Pd/Cucatalysed oxidative homo-coupling of two alkyne moieties yields the corresponding dimers. Hence, a model of an unsaturated polyester chain is cross-linked in a well-defined, metal-mediated reaction in a very high yield.

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Imidazolium Dichromate Adsorbed on Alumina: A Convenient and Inexpensive Reagent for the Cleavage of C=N Functionalities
Surya Kanta De
[Full text article]

Oximes, hydrazones and semicarbazones are converted to the corresponding carbonyl compounds using imidazolium dichromate adsorbed on alumina (IDC/alumina).

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A Simple Approach to DC-Cholesterol, its Analogues and Vitamin D-Based Cationic Lipids for Gene Therapy
Armandodoriano Bianco, Francesco Bonadies, Raffaella Napolitano and Giancarlo Ortaggi
[Full text article]

An improved synthesis of DC-Cholesterol, its analogues and Vitamin D-based lipids for the preparation of liposomes in gene therapy, is described. This synthetic strategy affords significative increase in the yields of DC-Cholesterol and its analogs.

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Design and Synthesis of a New Furanosic Sialylmimetic as a Potential Influenza Neuraminidase Viral Inhibitor
A. Bianco, M. Brufani, D.A. Dri, C. Melchioni and L. Filocamo
[Full text article]

A furanosic derivative has been identified as a simple sialylmimetic and synthesized, representing the first step in the development of a new series of furanosic sialic acid’s mimetics as potential inhibitors of influenza virus neuraminidase. The structure was tested on a molecular simulating environment before proceeding with synthetic pathways.

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Baker's Yeast Reduction of PEG-Linked Acetoacetate
G.M. Bonora, S. Drioli, C. Forzato, P. Nitti and G. Pitacco
[Full text article]

Bioreduction of PEG-acetoacetate 1 is achieved using dry baker's yeast in toluene with a small amount of added water. After detachment from the polymer under basic conditions, the corresponding (S)-(+)- 3-hydroxybutanoic acid 3 was esterified with Me3SiCl and ethanol and ethyl (S)-(+)-3-hydroxybutanoate 4 was isolated with 97% e.e. and 70% overall yield.